Hi, I found that we have an option named opengl. What is that for? So if I put "opengl=1" in my VM configuration file, what advantage my VM will get?? Thanks, Jun _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Jun Koi wrote:> Hi, > > I found that we have an option named opengl. What is that for? So if I > put "opengl=1" in my VM configuration file, what advantage my VM will > get?? >opengl=1 is the default and makes qemu render the guest framebuffer using opengl. Otherwise if you set opengl=0 qemu will use the sdl library. opengl=1 makes sense if you don''t use vnc and you have good drivers for your graphic card in dom0. _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
On Thu, Dec 11, 2008 at 7:33 PM, Stefano Stabellini <stefano.stabellini@eu.citrix.com> wrote:> Jun Koi wrote: > >> Hi, >> >> I found that we have an option named opengl. What is that for? So if I >> put "opengl=1" in my VM configuration file, what advantage my VM will >> get?? >> > > opengl=1 is the default and makes qemu render the guest framebuffer > using opengl.OK, so the patch you posted on QEMU mailing list is to enable this function on QEMU.> Otherwise if you set opengl=0 qemu will use the sdl library. > opengl=1 makes sense if you don''t use vncSo this means "opengl=1" (default) and "vnc=0" will give a better performance than "vnc=1, sdl=0", right?>and you have good drivers for > your graphic card in dom0.I am using Ubuntu 8.10 with chipset Intel 945GM, so certainly I have "good driver", right? Many thanks, Jun _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Jun Koi wrote:> On Thu, Dec 11, 2008 at 7:33 PM, Stefano Stabellini > <stefano.stabellini@eu.citrix.com> wrote: >> Jun Koi wrote: >> >>> Hi, >>> >>> I found that we have an option named opengl. What is that for? So if I >>> put "opengl=1" in my VM configuration file, what advantage my VM will >>> get?? >>> >> opengl=1 is the default and makes qemu render the guest framebuffer >> using opengl. > > OK, so the patch you posted on QEMU mailing list is to enable this > function on QEMU.Yes.>> Otherwise if you set opengl=0 qemu will use the sdl library. >> opengl=1 makes sense if you don''t use vnc > > So this means "opengl=1" (default) and "vnc=0" will give a better > performance than "vnc=1, sdl=0", right?Just to be clear opengl is used only together with sdl: sdl is still needed to create the window. So the three possibilities are: /* window on the host screen, opengl acceleration */ sdl=1 opengl=1 vnc=0 /* window on the host screen, no opengl acceleration */ sdl=1 opengl=0 vnc=0 /* no window on the host screen just a vnc server */ sdl=0 (opengl does not matter) vnc=0>> and you have good drivers for >> your graphic card in dom0. > > I am using Ubuntu 8.10 with chipset Intel 945GM, so certainly I have > "good driver", right? >If you are using the intel driver (intel, i815, i915, etc.) in xorg, yes; if you are using the vesa driver, no. If you are using opengl=1 and the vesa driver in xorg, you''ll notice because it is really slow. _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
On Thu, Dec 11, 2008 at 8:11 PM, Stefano Stabellini <stefano.stabellini@eu.citrix.com> wrote:> Jun Koi wrote: > >> On Thu, Dec 11, 2008 at 7:33 PM, Stefano Stabellini >> <stefano.stabellini@eu.citrix.com> wrote: >>> Jun Koi wrote: >>> >>>> Hi, >>>> >>>> I found that we have an option named opengl. What is that for? So if I >>>> put "opengl=1" in my VM configuration file, what advantage my VM will >>>> get?? >>>> >>> opengl=1 is the default and makes qemu render the guest framebuffer >>> using opengl. >> >> OK, so the patch you posted on QEMU mailing list is to enable this >> function on QEMU. > > Yes. > >>> Otherwise if you set opengl=0 qemu will use the sdl library. >>> opengl=1 makes sense if you don''t use vnc >> >> So this means "opengl=1" (default) and "vnc=0" will give a better >> performance than "vnc=1, sdl=0", right? > > > Just to be clear opengl is used only together with sdl: sdl is still > needed to create the window. > So the three possibilities are: > > /* window on the host screen, opengl acceleration */ > sdl=1 opengl=1 vnc=0 >OK, and this gives us the best performance.> /* window on the host screen, no opengl acceleration */ > sdl=1 opengl=0 vnc=0 > > /* no window on the host screen just a vnc server */ > sdl=0 (opengl does not matter) vnc=0 > > >>> and you have good drivers for >>> your graphic card in dom0. >> >> I am using Ubuntu 8.10 with chipset Intel 945GM, so certainly I have >> "good driver", right? >> > > If you are using the intel driver (intel, i815, i915, etc.) in xorg, > yes; if you are using the vesa driver, no. > > If you are using opengl=1 and the vesa driver in xorg, you''ll notice > because it is really slow.So I understand that if your patches to QEMU are merged, QEMU/KVM would get much better graphical performance. Excellent! Did you benchmark to see how much it is better? Any number? Thanks, Jun _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel
Jun Koi wrote:>> /* window on the host screen, opengl acceleration */ >> sdl=1 opengl=1 vnc=0 >> > > OK, and this gives us the best performance.Yes.> > So I understand that if your patches to QEMU are merged, QEMU/KVM > would get much better graphical performance. Excellent! Did you > benchmark to see how much it is better? Any number? >Yes, but don''t hold your breath, qemu people didn''t seem very interested in this. It is difficult to get any significant number, but I can tell you that at least you can get window resizing for free, not to mention many possible further improvements. _______________________________________________ Xen-devel mailing list Xen-devel@lists.xensource.com http://lists.xensource.com/xen-devel